Organic light-emitting display apparatus and method of manufacturing the same

ABSTRACT

An organic light-emitting display apparatus includes a substrate, a display on the substrate, a dam outside the display and spaced from the display, the dam having a stacked multi-layer structure and having a first side surface that faces the display, a second side surface opposite to the display, and a top, a groove in a separation area between the display and the dam, and an encapsulation layer that includes a first inorganic layer and an organic layer on the first inorganic layer, the first inorganic layer covering the display and extending along an inner surface of the groove, and an end of the organic layer being contained in the groove.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean PatentApplication No. 10-2015-0031970, filed on Mar. 6, 2015, in the KoreanIntellectual Property Office, the disclosure of which is incorporatedherein in its entirety by reference.

BACKGROUND

1. Field

One or more exemplary embodiments relate to an organic light-emittingdisplay apparatus and a method of manufacturing the same.

2. Description of the Related Art

Because organic light-emitting display apparatuses have wide viewingangles, good contrast, and fast response times, the organiclight-emitting display apparatuses are attracting much attention asnext-generation display apparatuses.

Generally, in an organic light-emitting display apparatus, a pluralityof thin film transistors (TFTs) and a plurality of organiclight-emitting devices are formed on a lower substrate, and the organiclight-emitting devices self-emit light. The organic light-emittingdisplay apparatus may be used as a display of a small product such as aportable terminal and as a display of a large product such as a TV.

The organic light-emitting devices are vulnerable to external moistureand oxygen. Therefore, an encapsulation layer is formed on an organiclight-emitting device, thereby covering the organic light-emittingdevice, and protecting the organic light-emitting device from externalmoisture and oxygen.

However, in a typical organic light-emitting display apparatus and amethod of manufacturing the same, because a thickness of anencapsulation layer covering an organic light-emitting device isinsufficient, cracks occur in the encapsulation layer due toparticle-type impurities flowing from the outside, and external moistureand oxygen penetrate into a display through the cracks. As such, adefect rate of an organic light-emitting display apparatus increases,and a service life of the organic light-emitting display apparatus isshortened.

SUMMARY

One or more exemplary embodiments include an organic light-emittingdisplay apparatus with an enhanced sealing force and a method ofmanufacturing the same.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description, or may belearned by practice of the presented embodiments.

According to one or more exemplary embodiments of the present invention,an organic light-emitting display apparatus includes: a substrate; adisplay on the substrate; a dam outside the display and spaced from thedisplay, the dam having a stacked multi-layer structure and having afirst side surface that faces the display, a second side surfaceopposite to the display, and a top; a groove in a separation areabetween the display and the dam; and an encapsulation layer thatincludes a first inorganic layer and an organic layer on the firstinorganic layer, the first inorganic layer covering the display andextending along an inner surface of the groove, and an end of theorganic layer being contained in the groove.

A first portion of the first inorganic layer may cover the first sidesurface of the dam, a second portion of the first inorganic layer maycover the second side surface of the dam, and a third portion of thefirst inorganic layer may cover the top of the dam.

The organic light-emitting display apparatus may further include asecond inorganic layer on the organic layer, wherein a first portion ofthe second inorganic layer may be on the second portion of the firstinorganic layer and a second portion of the second inorganic layer maybe on the third portion of the first inorganic layer.

A top of the organic layer may be substantially flat.

The dam may include a recessed portion at the top of the dam.

The organic layer may not be on the second side surface of the dam.

The organic light-emitting display apparatus may further include: ametal layer on a side of the display, the metal layer being configuredto supply power to the display; and an insulation layer under the metallayer, wherein the separation area may expose the metal layer or theinsulation layer.

The display may include: a thin film transistor on the substrate; apixel electrode electrically connected to the thin film transistor; apixel definition layer that covers an edge of the pixel electrode andexposes a portion of the pixel electrode; an intermediate layer on thepixel electrode, the intermediate layer including an emission layer; andan opposite electrode opposite to the pixel electrode. The dam mayinclude:

a first layer extending in a direction parallel to a plane of thesubstrate and including an organic insulation material; and a secondlayer on the first layer and including a material that is the same as amaterial of the pixel definition layer.

A height of the dam from a top of the substrate to the top of the dammay be greater than a height from the top of the substrate to a bottomof the pixel definition layer.

A first portion of the organic layer at the pixel definition layer mayhave a first thickness, a second portion of the organic layer at theseparation area may have a second thickness, and a third portion of theorganic layer at an edge of the display without the pixel definitionlayer thereon may have a third thickness, and the third thickness may begreater than the first thickness and less than the second thickness.

The organic light-emitting display apparatus may further include aninsulation layer that covers the thin film transistor and planarizes atop of the thin film transistor, wherein the pixel definition layer maybe on the insulation layer, a first portion of the organic layer at thepixel definition layer may have a first thickness, a second portion ofthe organic layer at the separation area may have a second thickness,and a third portion of the organic layer on the insulation layer at anedge of the display may have a third thickness, and the third thicknessmay be greater than the first thickness and less than the secondthickness.

According to one or more exemplary embodiments, a method ofmanufacturing an organic light-emitting display apparatus includes:forming a display on a substrate; forming a dam outside the display, thedam being spaced apart from the display and having a stacked multi-layerstructure; and forming an encapsulation layer, the encapsulation layerincluding: a first inorganic layer covering the display and extendingalong an inner surface of a groove; and an organic layer on the firstinorganic layer, wherein the groove is at a separation area between thedisplay and the dam, wherein an end of the organic layer is contained inthe groove, and wherein the dam has a first side surface that faces thedisplay, a second side surface opposite to the display, and a top.

A first portion of the first inorganic layer may cover the first sidesurface of the dam, a second portion of the first inorganic layer maycover the second side surface of the dam, and a third portion of thefirst inorganic layer may cover the top of the dam.

The forming of the encapsulation layer may include forming a secondinorganic layer on the organic layer, and a first portion of the secondinorganic layer may be on the second portion of the first inorganiclayer and a second portion of the second inorganic layer may be on thethird portion of the first inorganic layer.

A top of the organic layer may be substantially flat.

The method may further include: forming a metal layer on a side of thedisplay, the metal layer being configured to supply power to thedisplay; and forming an insulation layer under the metal layer, whereinthe separation area may expose the metal layer or the insulation layer.

The forming of the display may include: forming a thin film transistoron the substrate; forming a pixel electrode that is electricallyconnected to the thin film transistor; forming a pixel definition layer,which covers an edge of the pixel electrode and exposes a portion of thepixel electrode; forming an intermediate layer on the pixel electrode,the intermediate layer including an emission layer; and forming anopposite electrode opposite to the pixel electrode. The forming of thedam may include: forming a first layer that extends in a directionparallel to a plane of the substrate and including an organic insulationmaterial; and forming a second layer on the first layer, the secondlayer including a material that is the same as a material of the pixeldefinition layer, the second layer and the pixel definition layer beingformed concurrently.

A height of the dam from a top of the substrate to the top of the dammay be greater than a height from the top of the substrate to a bottomof the pixel definition layer.

A first portion of the organic layer at the pixel definition layer mayhave a first thickness, a second portion of the organic layer at theseparation area may have a second thickness, and a third portion of theorganic layer at an edge of the display without the pixel definitionlayer thereon may have a third thickness, and the third thickness may begreater than the first thickness and less than the second thickness.

The forming of the display and the forming of the dam may beconcurrently performed.

In addition to the aforesaid details, other aspects and features will beclarified from the following drawings, claims, and detailed description.

These general and specific embodiments may be implemented by using asystem, a method, a computer program, or a combination of the system,the method, and the computer program.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects will become apparent and more readilyappreciated from the following description of the exemplary embodiments,taken in conjunction with the accompanying drawings in which:

FIG. 1 is a cross-sectional view schematically illustrating an organiclight-emitting display apparatus according to one or more exemplaryembodiments;

FIG. 2 is an enlarged cross-sectional view schematically illustrating astructure in region II of FIG. 1 in which an encapsulation layer isexcluded;

FIG. 3 is an enlarged cross-sectional view schematically illustrating astructure in region II of FIG. 1 in which the encapsulation layer isincluded;

FIG. 4 is a cross-sectional view schematically illustrating an organiclight-emitting display apparatus according to one or more exemplaryembodiments;

FIG. 5 is a cross-sectional view schematically illustrating a structurein region V of FIG. 4 in which an encapsulation layer is excluded; and

FIG. 6 is a cross-sectional view schematically illustrating a structurein the region V in which the encapsulation layer is included.

DETAILED DESCRIPTION

Reference is now made in detail to exemplary embodiments, examples ofwhich are illustrated in the accompanying drawings, wherein likereference numerals refer to like elements throughout. In this regard,the present exemplary embodiments may have different forms and shouldnot be construed as being limited to the descriptions set forth herein.Accordingly, the exemplary embodiments are merely described below, byreferring to the figures, to explain aspects of the present description.

Since the inventive concept may have diverse modified embodiments,example embodiments are illustrated in the drawings and are described inthe detailed description of the inventive concept. The features andaspects of the inventive concept will become apparent from the followingdescription of the embodiments with reference to the accompanyingdrawings, which is set forth hereinafter. The inventive concept may,however, be embodied in different forms and should not be construed aslimited to the embodiments set forth herein.

The terminology used herein is for the purpose of describing particularembodiments and is not intended to be limiting of the inventive concept.

It will be understood that although the terms “first”, “second”, etc.may be used herein to describe various components, these componentsshould not be limited by these terms. These terms are only used todistinguish one component from another. The terms of a singular form mayinclude plural forms unless referred to the contrary.

The meaning of ‘comprise’, ‘include’, or ‘have’ specifies a property, aregion, a fixed number, a step, a process, an element and/or a componentbut does not exclude other properties, regions, fixed numbers, steps,processes, elements and/or components. In the following embodiments,when an element such as a layer or a region is referred to as being“on”, “connected to” or “adjacent to” another element, it can bedirectly on, connected to, or adjacent to the other element or layer, orone or more intervening elements or layers may be present. When anelement or layer is referred to as being “directly on,” “directlyconnected to”, or “immediately adjacent to” another element or layer,there are no intervening elements or layers present. As used herein, theterm “and/or” includes any and all combinations of one or more of theassociated listed items. Expressions such as “at least one of,” whenpreceding a list of elements, modify the entire list of elements and donot modify the individual elements of the list. Further, the use of“may” when describing embodiments of the inventive concept refers to“one or more embodiments of the inventive concept.” Also, the term“exemplary” is intended to refer to an example or illustration.

As used herein, the terms “substantially,” “about,” and similar termsare used as terms of approximation and not as terms of degree, and areintended to account for the inherent variations in measured orcalculated values that would be recognized by those of ordinary skill inthe art.

Sizes of elements in the drawings may be exaggerated for convenience ofexplanation. In other words, because sizes and thicknesses of componentsin the drawings may be arbitrarily illustrated for convenience ofexplanation, the following embodiments are not limited thereto.Spatially relative terms, such as “below,” “lower,” “bottom,” “above,”“upper,” “top,” and the like, may be used herein for ease of explanationto describe one element or feature's relationship to another element(s)or feature(s) as illustrated in the figures. It will be understood thatthe spatially relative terms are intended to encompass differentorientations of the device in use or in operation, in addition to theorientation depicted in the figures. For example, if the device in thefigures is turned over, elements described as “below” other elements orfeatures would then be oriented “above” the other elements or features.Thus, the example term “below” can encompass both an orientation ofabove and below. The device may be otherwise oriented (e.g., rotated 90degrees or at other orientations) and the spatially relative descriptorsused herein should be interpreted accordingly.

In the following examples, the x-axis, the y-axis, and the z-axis arenot limited to three axes of the rectangular coordinate system, and maybe interpreted in a broader sense. For example, the x-axis, the y-axis,and the z-axis may be perpendicular to one another, or may representdifferent directions that are not perpendicular to one another.

When a certain embodiment may be implemented differently, a specificprocess order may be performed differently from the described order. Forexample, two consecutively described processes may be performedsubstantially at the same time or performed in an order opposite to thedescribed order.

FIG. 1 is a cross-sectional view schematically illustrating an organiclight-emitting display apparatus according to one or more exemplaryembodiments of the present invention.

Referring to FIG. 1, the organic light-emitting display apparatusaccording to one or more exemplary embodiments of the present inventionmay include a substrate 100, a display 200 disposed on the substrate100, an encapsulation layer 300 disposed on the display 200, a dam (orbarrier) 400 disposed outside of the display 200, and a groove 500 at aseparation area SA between the display 200 and the dam 400.

The substrate 100 may be formed of various materials such as a glassmaterial, a metal material, etc. Alternatively, the substrate 100 mayhave a flexible characteristic, and therefore, the substrate 100 may beformed of one or more of various suitable materials such as a metalmaterial and plastic materials such as, for example, polyethyleneterephthalate (PET), polyethylene naphthalate (PEN), polyimide, etc. Thesubstrate 100 may include a display area DA in which the display 200 isdisposed and a peripheral area PA which surrounds (or encircles) thedisplay area DA (e.g., surrounds the display area DA in a plane). Thedisplay 200 may include a plurality of organic light-emitting devicesOLED. The display 200 may be disposed on the substrate 100 and mayinclude the plurality of organic light-emitting devices OLED. In one ormore exemplary embodiments, the display 200 may be an organiclight-emitting display that includes a plurality of thin filmtransistors TFT and a plurality of pixel electrodes 210 (see FIG. 2)respectively connected thereto, but the display 200 is not limitedthereto. For example, the display 200 may be an organic light-emittingdisplay or may be a liquid crystal display. A detailed structure of thedisplay 200 according to one or more embodiments of the presentinvention is described further below with reference to FIGS. 2 and 3.

The encapsulation layer 300 may be disposed on the display 200 to coverthe display 200. That is, the encapsulation layer 300 may cover a top ofthe display 200 and may seal the organic light-emitting device OLED, andat least one portion of the encapsulation layer 300 may be disposedadjacent to the substrate 100. The encapsulation layer 300 may be formedin a multi-layer structure where an organic layer and an inorganic layerare stacked, thereby enhancing a sealing force.

The dam 400 may be disposed outside the display 200 and separated fromthe display 200 (e.g., may be separated from the display 200 by apredetermined distance). The separation area SA may be formed betweenthe dam 400 and the display 200, and the groove 500 may be formed in theseparation area SA. At least one portion of the encapsulation layer 300may be buried or contained in the groove 500.

FIG. 2 is an enlarged cross-sectional view schematically illustrating astructure in region II of FIG. 1 in which the encapsulation layer 300 isexcluded. FIG. 3 is an enlarged cross-sectional view schematicallyillustrating a structure in region II of FIG. 1 in which theencapsulation layer 300 is included.

FIG. 2 illustrates a structure of each of the display 200 and the dam400 but not the encapsulation layer 300 of the organic light-emittingdisplay apparatus of FIG. 1. According to one or more exemplaryembodiments of the present invention, the display 200 may be disposed inthe display area DA of the substrate 100. A general structure of thedisplay 200 is described below with reference to FIG. 2.

The display 200 may include a thin film transistor TFT and a capacitorCAP, and an organic light-emitting device OLED that is electricallyconnected to the thin film transistor TFT may be disposed in the display200. The thin film transistor TFT may include a semiconductor layer 120,a gate electrode 140, a source electrode 160, and a drain electrode 162.The semiconductor layer may include amorphous silicon, polycrystallinesilicon, and/or an organic semiconductor material, for example. Ageneral configuration of the thin film transistor TFT is describedfurther below.

A buffer layer 110 may be disposed on the top of the substrate 100 andmay be provided for planarizing a surface of the substrate 100 orpreventing impurities from penetrating into the thin film transistor TFTor the organic light-emitting device OLED, which are included in thedisplay 200 disposed on the substrate 100. The buffer layer 110 mayinclude a single layer or layers of a material such as silicon oxideand/or silicon nitride. The semiconductor layer 120 may be disposed onthe buffer layer 110.

The gate electrode 140 may be disposed on the semiconductor layer 120,and the source electrode 160 may be electrically connected to the drainelectrode 162 according to a signal applied to the gate electrode 140.The gate electrode 140 may include a single layer or layers of, forexample, one or more materials selected from aluminum (Al), platinum(Pt), palladium (Pd), silver (Ag), magnesium (Mg), gold (Au), nickel(Ni), neodymium (Nd), iridium (Ir), chromium (Cr), lithium (Li), calcium(Ca), molybdenum (Mo), titanium (Ti), tungsten (W), and copper (Cu) bytaking into account adhesiveness to a layer adjacent thereto, a surfaceflatness of a stacked layer, and processability.

In order to secure insulation between the semiconductor layer 120 andthe gate electrode 140, a gate insulation layer 130, formed of siliconoxide and/or silicon nitride, may be disposed between the semiconductorlayer 120 and the gate electrode 140.

An interlayer insulation layer 150 may be disposed on the gate electrode140 and may include a single layer or layers of a material such assilicon oxide and/or silicon nitride, for example.

The source electrode 160 and the drain electrode 162 may be disposed onthe interlayer insulation layer 150. The source electrode 160 and thedrain electrode 162 may be electrically connected to the semiconductorlayer 120 through a contact hole which is formed in the interlayerinsulation layer 150 and the gate insulation layer 130. The sourceelectrode 160 and the drain electrode 162 may include a single layer orlayers of, for example, one or more materials selected from aluminum(Al), platinum (Pt), palladium (Pd), silver (Ag), magnesium (Mg), gold(Au), nickel (Ni), neodymium (Nd), iridium (Ir), chromium (Cr), lithium(Li), calcium (Ca), molybdenum (Mo), titanium (Ti), tungsten (W), andcopper (Cu) by taking into account conductivity.

A passivation layer may be disposed covering the thin film transistorTFT to protect the thin film transistor TFT having the above-describedstructure. The passivation layer may be formed of, for example, aninorganic material such as silicon oxide, silicon nitride, and/orsilicon oxynitride.

A planarization layer 170 may be disposed on the substrate 100. In thiscase, the planarization layer 170 may be a passivation layer. When theorganic light-emitting device OLED is disposed on the thin filmtransistor TFT, the planarization layer 170 planarizes an entire uppersurface of the thin film transistor TFT (e.g., the whole top of the thinfilm transistor TFT) and protects the thin film transistor TFT andvarious devices. The planarization layer 170 may be formed of an organicinsulating material, and for example, may be formed of an acryl-basedorganic material and/or benzocyclobutene (BCB). As illustrated in FIG.2, in one or more exemplary embodiments, the buffer layer 110, the gateinsulation layer 130, the interlayer insulation layer 150, and theplanarization layer 170 may be formed over an entire surface of thesubstrate 100 (e.g., over the whole substrate 100).

A pixel definition layer 180 may be disposed on the thin film transistorTFT. The pixel definition layer 180 may be disposed on theabove-described planarization layer 170 and may have an opening. Thepixel definition layer 180 may define a pixel area on the substrate 100.

The pixel definition layer 180 may be provided as, for example, anorganic insulation layer. The organic insulation layer may include anacryl-based polymer such as poly(methyl methacrylate) (PMMA),polystyrene (PS), polymer derivatives containing a phenol group, animide-based polymer, an aryl ether-based polymer, an amide-basedpolymer, a fluorine-based polymer, a p-xylene-based polymer, a vinylalcohol-based polymer, and/or a compound thereof.

The organic light-emitting device OLED may be disposed on the pixeldefinition layer 180. The organic light-emitting device OLED may includea pixel electrode 210, an intermediate layer 220 including an emissionlayer (EML), and an opposite electrode 230.

The pixel electrode 210 may be formed as a semi-transparent electrode, atransparent electrode or a reflective electrode. When the pixelelectrode 210 is formed as a semi-transparent electrode or a transparentelectrode, the pixel electrode 210 may be formed of, for example, indiumtin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium oxide(In₂O₃), indium gallium oxide (IGO), and/or aluminum zinc oxide (AZO).When the pixel electrode 210 is formed as a reflective electrode, thepixel electrode 210 may include a reflective layer formed of Ag, Mg, Al,Pt, Pd, Au, Ni, Nd, Ir, Cr, and/or a compound thereof, and a layerformed of ITO, IZO, ZnO, In₂O₃, IGO, and/or AZO. However, the presentinvention is not limited thereto, and the pixel electrode 210 may beformed of various suitable materials. Also, a structure of the pixelelectrode 210 may include a single layer or layers.

The intermediate layer 220 may be disposed in the pixel area defined bythe pixel definition layer 180. The intermediate layer 220 may includethe EML that emits light according to an electrical signal. In additionto the EML, a hole injection layer (HIL) disposed between the EML andthe pixel electrode 210, an electron transport layer (ETL) disposedbetween the opposite electrode 230 and the HTL and EML, and/or anelectron injection layer (EIL) may be stacked and formed in a single orcomplex structure. However, the intermediate layer 220 is not limitedthereto, and may have various structures.

The intermediate layer 220 may be formed of a low-molecular weightorganic material and/or a polymer organic material.

When the intermediate layer 220 includes a low-molecular weight organicmaterial, an HTL, an HIL, an ETL, and/or an EIL may be stacked withrespect to the EML, and the layers may be stacked in various suitablearrangements. The intermediate layer 220 may use, as an availableorganic material, various suitable materials such as copperphthalocyanine (CuPc), N,N′-Di(naphthalene-1-yl)-N,N′-diphenyl-benzidine(NPB), and/or tris-8-hydroxyquinoline aluminum (Alq3).

When the intermediate layer 220 includes a polymer organic material, anHTL in addition to the intermediate layer 220 may be provided. The HTLmay use poly-(2,4)-ethylene-dihydroxy thiophene (PEDOT) and/orpolyaniline (PANI). In this case, the intermediate layer 220 may use, asan available organic material, polymer organic materials such as a poly(p-phenylene vinylene) (PPV)-based polymer material and/or apolyfluorene-based polymer material. Also, in one or more exemplaryembodiments, an inorganic material may be provided between theintermediate layer 220 and the pixel electrode 210 and the oppositeelectrode 230.

In one or more exemplary embodiments, the HTL, the HIL, the ETL, and/orthe EIL may be formed as one body over the whole substrate 100, and onlythe EML may be formed in each pixel in an inkjet printing process. TheHTL, the HIL, the ETL, and/or the EIL may be disposed in the pixel area.

The opposite electrode 230, which covers the intermediate layer 220including the EML and opposite to the pixel electrode 210, may bedisposed over the whole substrate 100. The opposite electrode 230 may beformed as a semi-transparent electrode, a transparent electrode or areflective electrode.

When the opposite electrode 230 is formed as a semi-transparent or atransparent electrode, the opposite electrode 230 may include a layerformed of metal (e.g., Li, Ca, LiF/Ca, LiF/Al, Al, Ag, Mg, and acompound thereof) having a small work function and a semi-transparent ortransparent conductive layer formed of ITO, IZO, ZnO, and/or In₂O₃. Whenthe opposite electrode 230 is formed as a reflective electrode, theopposite electrode 230 may include a layer formed of Li, Ca, LiF/Ca,LiF/Al, Al, Ag, Mg, and/or a compound thereof. However, a structure andmaterial of the opposite electrode 230 are not limited thereto, and maybe variously modified in any suitable manner.

A metal layer 165 may be disposed at a distal end of the display 200.The metal layer 165 may be disposed on the same layer as that of thesource electrode 160 and drain electrode 162 of the thin film transistorTFT, but in some embodiments the metal layer 165 may be disposed on thesame layer as that of the gate electrode 140. The metal layer 165 maysupply electrode power to the display 200. The metal layer 165 may beformed to extend to the dam 400, and as illustrated in FIG. 2, an edgeof the metal layer 165 may be covered by the dam 400. The metal layer165 may be exposed in the separation area SA (in other words, a portionof the metal layer 165 that is formed in the separation area SA may beexposed). In one or more exemplary embodiments, the metal layer 165 maynot extend to the dam 400, and the edge of the metal layer 165 may beexposed in the separation area SA. As such, the metal layer 165 and atleast a portion of the interlayer insulation layer 150 that is disposedunder the metal layer 165 may be exposed in the separation area SA.

Referring to FIG. 2, in one or more exemplary embodiments, the organiclight-emitting display apparatus may include the dam 400 which isdisposed outside the display 200 and separated from the display 200(e.g., separated from the display 200 by a predetermined distance). Thedam 400 may have a similar multi-layer structure to that of the display200. That is, the dam 400 may include a first layer 181, which extendsin a direction parallel to the plane of the substrate 100 and includesan organic insulation material, and a second layer 182 which is disposedon the first layer 181 and includes the same material as that of thepixel definition layer 180. The first layer 181 of the dam 400 mayinclude all or some of the layers included in the display 200. The dam400 prevents or substantially prevents an organic layer 320 of theencapsulation layer 300 from being abnormally (or inadvertently) spreadto an edge of the substrate 100.

The first layer 181 of the dam 400 may be formed of an organicinsulation material, and in one or more embodiments, the first layer 181may be formed in a multi-layer structure. In addition to the bufferlayer 110 that is disposed over the whole display area DA, the gateinsulation layer 130 and the interlayer insulation layer 150 may bedisposed between the first layer 181 and the substrate 100. The secondlayer 182 including the same material as that of the pixel definitionlayer 180 may be disposed on the first layer 181.

Therefore, a height h1 of the dam 400 from the top of the substrate 100to a top of the second layer 182 may be greater than a height h2 fromthe top of the substrate 100 to a top of the planarization layer 170. Inother words, the height h1 of the dam 400 from the top of the substrate100 to the top of the second layer 182 may be greater than the height h2from the top of the substrate 100 to a bottom of the pixel definitionlayer 180.

The separation area SA may be formed between the display 200 and the dam400 on the substrate 100, and, as illustrated in FIG. 2, the metal layer165 may be exposed in the separation area SA. In one or moreembodiments, the separation area SA may expose the substrate 100 and mayexpose the interlayer insulation layer 150 or the gate insulation layer130 disposed under the metal layer 165. The groove 500, whichcorresponds to a space between the display 200 and the dam 400, may beformed in the separation area SA. The groove 500 may include a distalend side surface 200 a of the display 200, a bottom 165 a of the groove500 where a portion of the buffer layer 110 or the substrate 100 isexposed in the separation area SA, and an inner surface 500 a whichincludes a first side surface 400 a of the dam 400 in a direction of thedisplay 200.

Referring to FIG. 3, the organic light-emitting display apparatus isillustrated including the encapsulation layer 300. That is, theencapsulation layer 300 may be disposed on the display 200 of FIG. 2.The encapsulation layer 300 may cover the display 200 and include afirst inorganic layer 310, an organic layer 320, and a second inorganiclayer 330, which are sequentially disposed.

The first inorganic layer 310 may be disposed over the whole substrate100 on the opposite electrode 230. The first inorganic layer 310 maycover an entire surface of the display 200 including the oppositeelectrode 230 and extend along the inner surface 500 a of the groove500. The first inorganic layer 310 may be disposed to cover the firstside surface 400 a of the dam 400 in the direction of the display 200, asecond side surface 400 b of the dam 400 opposite to the display 200,and a top 400 c of the dam 400 (e.g., a first portion of the firstinorganic layer 310 may cover the first side surface 400 a of the dam400, a second portion of the first inorganic layer 310 may cover thesecond side surface 400 b of the dam 400, and a third portion of thefirst inorganic layer 310 may cover the top 400 c of the dam 400).

The first inorganic layer 310 and the second inorganic layer 330 may beformed of an inorganic insulation material, and for example, may beformed of silicon nitride, aluminum nitride, zirconium nitride, titaniumnitride, hafnium nitride, tantalum nitride, silicon oxide, aluminumoxide, titanium oxide, tin oxide, cerium oxide, and/or siliconoxynitride (SiON).

The organic layer 320 may be disposed on the first inorganic layer 310.The organic layer 320 may be formed of a liquid organic material, andfor example, may be formed of acryl-based resin, methacrylate-basedresin, polyisoprene, vinyl-based resin, epoxy-based resin,urethane-based resin, cellulose-based resin, perylene-based resin,and/or imide-based resin. An organic material may be applied to a panelthrough a deposition process, a printing process, and/or a coatingprocess and may undergo a hardening process. When the organic materialis hardened after the organic material is more broadly spread than aninorganic layer in a liquid state before hardening, the panel is shrunkby evaporation of moisture. Therefore, according to one or moreexemplary embodiments of the present invention, the dam 400 prevents orsubstantially prevents a liquid organic material from being spread (orabnormally spread).

An end of the organic layer 320 may be buried or contained in the groove500. The organic layer 320 may follow or correspond to any curves ofstructures that are formed on the substrate 100, and a top of theorganic layer 320 may be substantially flat. Therefore, thicknesses ofrespective portions of the organic layer 320 may differ depending onshapes of the structures which are formed on the substrate 100. A firstportion of the organic layer 320 disposed at or on the pixel definitionlayer 180 may have a first thickness t1, a second portion of the organiclayer 320 at or in the separation area SA may have a second thicknesst2, and a third portion of the organic layer 320 at or on an edge of thedisplay 200 where the pixel definition layer 180 is not disposed mayhave a third thickness t3. The third thickness t3 may be greater thanthe first thickness t1 and less than the second thickness t2. The thirdthickness t3 corresponds to a portion (e.g., the third portion of theorganic layer 320) that is disposed on the planarization layer 170,which is an insulation layer disposed at the edge of the display 200.

The second inorganic layer 330 may be disposed on the organic layer 320.The second inorganic layer 330 may cover the organic layer 320, and anend of the second inorganic layer 330 may be disposed on the firstinorganic layer 310, which is disposed to cover a top of the dam 400 anda side surface opposite to the direction of the display 200 (e.g., afirst portion of the second inorganic layer 330 may be disposed on thesecond portion of the first inorganic layer 310 that covers the secondside surface 400 b of the dam 400 and a second portion of the secondinorganic layer 330 may be disposed on the third portion of the firstinorganic layer 310 that covers the top 400 c of the dam 400). A distalend of the second inorganic layer 330 may contact the substrate 200, anda sealing force is enhanced by a multi-layer structure of the firstinorganic layer 310, the organic layer 320, and the second inorganiclayer 330 of the encapsulation layer 300.

Generally, in manufacturing an organic light-emitting display apparatus,a display may be formed by using a mask. In depositing each layer of thedisplay with the mask, because the mask may sag, scratches may occur dueto contact between the mask and a pixel definition layer portion whichprotrudes the most from the display, thereby leaving particles on asurface of the mask. The particles are then transferred to another panelin a manufacturing process of forming a plurality of layers with onemask. When such an operation is repeated, the particles make the surfaceof the mask non-uniform, and scratches of the display are progressivelydeepened. Also, when the particles are of a certain size or larger, anencapsulation layer cannot normally seal the display due to theparticles, and a defect is caused by external moisture. Particularly, inareas progressively closer to the edge of the display, the thickness ofan organic layer of the encapsulation layer progressively decreases bythe spread of an organic insulation material. Thus, a probability thatparticles attached to a planarization layer disposed at an edge of thedisplay will cause a small defect increases.

Therefore, in the organic light-emitting display apparatus according toone or more exemplary embodiments of the present invention, the heightof the dam 400 outside the display 200 may be higher than that of theplanarization layer 170, and thus, the thickness of the organic layerdisposed in the edge of the display 200 and the peripheral area PA ofthe substrate 100 may be formed relatively thick. Therefore, in amanufacturing process, particles attached to the edge of the display 200may be buried or contained or deposited in the second portion of theorganic layer 320 having the second thickness t2 or in the third portionof the organic layer 320 having the third thickness t3, therebyminimizing or reducing a defect of a sealing force of the encapsulationlayer 300.

FIG. 4 is a cross-sectional view schematically illustrating an organiclight-emitting display apparatus according to one or more exemplaryembodiments of the present invention. FIG. 5 is an enlargedcross-sectional view schematically illustrating a structure in region Vof FIG. 4 in which an encapsulation layer 300 is excluded. FIG. 6 is anenlarged cross-sectional view schematically illustrating a structure inthe region V of FIG. 4 in which the encapsulation layer 300 is included.

Referring to FIGS. 4 to 6, the organic light-emitting display apparatusaccording to one or more exemplary embodiments may include a substrate100, a display 200 disposed on the substrate 100, the encapsulationlayer 300 disposed on the display 200, a dam 400, which is disposedoutside the display 200 and includes a recessed portion 410 at a top ofthe dam 400, and a groove 500 in a separation area SA between thedisplay 200 and the dam 400. The structures of various elements of theorganic light-emitting display according to the above-describedembodiment of FIGS. 1 to 3 are the same or substantially the same, withthe exception of the dam 400. As such, repeated description of likeelements is omitted below.

According to one or more exemplary embodiments, the dam 400 may bedisposed outside the display 200 and separated from the display 200(e.g., separated from the display 200 by a predetermined distance). Thedam 400 may have a similar multi-layer structure to that of the display200. That is, the dam 400 may include a first layer 181, which isdisposed in a direction of the substrate 100 including an organicinsulation material, and a second layer 182 which is disposed on thefirst layer 181 and includes the same material as that of the pixeldefinition layer 180. The first layer 181 of the dam 400 may include allor some of the layers included in the display 200. The dam 400 preventsan organic layer 320 of the encapsulation layer 300 from beingabnormally spread to an edge of the substrate 100.

The first layer 181 of the dam 400 may be formed of an organicinsulation material, and in some embodiments, the first layer 181 may beformed in a multi-layer structure. In addition to the buffer layer 110disposed over the whole display area DA, the gate insulation layer 130and the interlayer insulation layer 150 may be disposed between thefirst layer 181 and the substrate 100. The second layer 182 includingthe same material as that of the pixel definition layer 180 may bedisposed on the first layer 181.

Therefore, a height h1 of the dam 400 from the top of the substrate 100to a top of the second layer 182 may be greater than a height h2 fromthe top of the substrate 100 to a top of the planarization layer 170. Inother words, the height h1 of the dam 400 from the top of the substrate100 to the top of the second layer 182 may be greater than the height h2from the top of the substrate 100 to a bottom of the pixel definitionlayer 180. In one or more embodiments, a spacer may be further disposedon the second layer 182.

The recessed portion 410 may be formed in a top 400 c of the dam 400.Because the recessed portion 410 is formed in the top 400 c of the dam400, the organic layer 320 is prevented or substantially prevented frompassing over the dam 400 and spreading (e.g., abnormally orinadvertently spreading) to outside the dam 400.

The separation area SA may be formed between the display 200 and the dam400 on the substrate 100 and may expose the buffer layer 110. However,in some embodiments, the separation area SA may expose the substrate100. The groove 500, which corresponds to a space between the display200 and the dam 400, may be formed in the separation area SA. An innersurface 500 a of the groove 500 may include a distal end side surface200 a of the display 200, a bottom 165 a corresponding to the separationarea SA (e.g., where a portion of the buffer layer 110 or the substrate100 is exposed in the separation area SA), and a first side surface 400a of the dam 400. The inner surface 500 a of the groove 500 may extendin a direction of the display 200.

The encapsulation layer 300 may be disposed on the display 200. Theencapsulation layer 300 may cover the display 200 and may include afirst inorganic layer 310, an organic layer 320, and a second inorganiclayer 330, which are sequentially disposed.

The first inorganic layer 310 may be disposed over the whole substrate100 on the opposite electrode 230. The first inorganic layer 310 maycover an entire surface of the display 200 including the oppositeelectrode 230 and may extend along the inner surface 500 a of the groove500. The first inorganic layer 310 may be disposed to cover the firstside surface 400 a of the dam 400 in the direction of the display 200, asecond side surface 400 b of the dam 400 opposite to the display 200,and a top 400 c of the dam 400. Also, the first inorganic layer 310 maybe disposed in the recessed portion 410 which is disposed on the top 400c of the dam 400.

The first inorganic layer 310 and the second inorganic layer 330 may beformed of an inorganic insulation material, and for example, may beformed of silicon nitride, aluminum nitride, zirconium nitride, titaniumnitride, hafnium nitride, tantalum nitride, silicon oxide, aluminumoxide, titanium oxide, tin oxide, cerium oxide, and/or siliconoxynitride (SiON).

The organic layer 320 may be disposed on the first inorganic layer 310.The organic layer 320 may be formed of a liquid organic material, andfor example, may be formed of acryl-based resin, methacryl-based resin,polyisoprene, vinyl-based resin, epoxy-based resin, urethane-basedresin, cellulose-based resin, perylene-based resin, and/or imide-basedresin. An organic material may be applied to a panel through adeposition process, a printing process, and/or a coating process and mayundergo a hardening process. When the organic material is hardened afterthe organic material is more broadly spread than an inorganic layer in aliquid state before hardening, the panel is shrunk by evaporation ofmoisture. Therefore, according to one or more exemplary embodiments ofthe present invention, the dam 400 prevents or substantially prevents aliquid organic material from being spread (e.g., abnormally orinadvertently spread).

An end of the organic layer 320 may be buried or contained in the groove500. The organic layer 320 may follow or correspond to any curves ofstructures that are formed on the substrate 100, and a top of theorganic layer 320 may be substantially flat. Therefore, thicknesses ofrespective portions of the organic layer 320 may differ depending onshapes of the structures which are formed on the substrate 100. A firstportion of the organic layer 320 disposed at or on the pixel definitionlayer 180 may have a first thickness t1, a second portion of the organiclayer 320 disposed at or in the separation area SA may have a secondthickness t2, and a third portion of the organic layer 320 at or on anedge of the display 200 where the pixel definition layer 180 is notdisposed may have a third thickness t3. The third thickness t3 may begreater than the first thickness t1 and less than the second thicknesst2. The third thickness t3 corresponds to a portion (e.g., the thirdportion of the organic layer 320) that is disposed on an insulationlayer which is disposed at the edge of the display 200.

The end of the organic layer 320 may be formed to a height of the dam400, and in some embodiments, a portion of the organic layer 320 may bedisposed in the recessed portion 410. As such, an organic material thatmay pass over the dam 400 when forming the organic layer 320 may bedisposed in the recessed portion 410.

The second inorganic layer 330 may be disposed on the organic layer 320.The second inorganic layer 330 may cover the organic layer 320, and anend of the second inorganic layer 330 may be disposed on the firstinorganic layer 310, which is disposed to cover a top of the dam 400 anda side surface opposite to the direction of the display 200 (e.g., afirst portion of the second inorganic layer 330 may be disposed on thesecond portion of the first inorganic layer 310 that covers the secondside surface 400 b of the dam 400 and a second portion of the secondinorganic layer 330 may be disposed on the third portion of the firstinorganic layer 310 that covers the top 400 c of the dam 400). A distalend of the second inorganic layer 330 may contact the substrate 200, anda sealing force is enhanced by a multi-layer structure of the firstinorganic layer 310, the organic layer 320, and the second inorganiclayer 330 of the encapsulation layer 300.

The present invention is also directed to a method of manufacturing anorganic light-emitting display apparatus.

First, an operation of forming the display 200 on the substrate 100 maybe performed. The display 200 may include the thin film transistor TFT,the capacitor CAP, and the organic light-emitting device OLED that iselectrically connected to the thin film transistor TFT. The operation offorming the display 200 may include forming the thin film transistor TFTon the substrate 100 and then forming the pixel electrode that iselectrically connected to the thin film transistor TFT. Subsequently,the operation of forming the display 200 may include forming the pixeldefinition layer, which covers an edge of the pixel electrode andexposes a portion (e.g., a center portion) of the pixel electrode, andforming the intermediate layer, which includes the EML, on the centerportion of the pixel electrode exposed by the pixel definition layer.The operation of forming the display 200 may include forming theopposite electrode, which is opposite to the pixel electrode, over thewhole substrate 100 and on the intermediate layer. The above-describeddetails of FIG. 2 are repetitive of a detailed manufacturing process anda configuration of the display 200 which includes the thin filmtransistor TFT and the organic light-emitting device OLED. Accordingly,additional description thereof is omitted herein.

An operation of forming the dam 400, which has a multi-layer structure,outside the display 200 and separated from the display 200 may beperformed. The dam 400 may be concurrently formed with the operation offorming the display 200. The dam 400 may be formed of the layersincluded in the display 200. The dam 400 may undergo an operation offorming the first layer 181 in a direction of the substrate 100 and thenundergo an operation of forming the second layer 182, which includes thesame material as that of the pixel definition layer 180, on the firstlayer 181. The first layer 181 may have a multi-layer structure.

The height h1 of the dam 400 may be greater than the height h2 of theplanarization layer 170. In other words, a height from the top of thesubstrate 100 to the top of the dam 400 may be greater than the heighth2 from the top of the substrate 100 to the bottom of the pixeldefinition layer 180. The spacer may be further disposed on the secondlayer 182.

The separation area SA may be formed between the display 200 and the dam400 on the substrate 100, and as illustrated in FIG. 2, the separationarea SA may expose the metal layer 165. In some embodiments, theseparation area SA may expose the substrate 100 and expose theinterlayer insulation layer 150 or the gate insulation layer 130disposed under the metal layer 165. The groove 500, which corresponds toa space between the display 200 and the dam 400, may be formed in theseparation area SA. The inner surface 500 a of the groove 500 mayinclude the distal end side surface 200 a of the display 200, the bottom165 a corresponding to the separation area SA (e.g., where a portion ofthe buffer layer 110 or the substrate 100 is exposed in the separationarea SA), and the first side surface 400 a of the dam 400. The innersurface 500 a of the groove 500 may extend in a direction of the display200.

Subsequently, an operation of forming the encapsulation layer 300, whichcovers the display 200 and is buried or contained in the groove 500formed between the display 200 and the dam 400, may be performed. Theoperation of forming the encapsulation layer 300 may include anoperation of forming the first inorganic layer 310, an operation offorming the organic layer 320 on the first inorganic layer 310, and anoperation of forming the second inorganic layer 330 on the organic layer320.

The first inorganic layer 310 may be formed over the whole substrate 100and on the opposite electrode to cover the display 200, and may extendalong the inner surface 500 a of the groove 500, which is formed in theseparation area SA between the display 200 and the dam 400. The end ofthe first inorganic layer 310 may be formed to cover the first sidesurface 400 a of the dam 400 in the direction of the display 200, thesecond side surface 400 b of the dam 400 opposite to the display 200,and the top 400 c of the dam 400.

Subsequently, the organic layer 320 may be formed on the first inorganiclayer 310, and the end of the organic layer 320 may be buried orcontained in the groove 500. The organic layer 320 may correspond to anycurves of structures that are formed on the substrate 100, and a top ofthe organic layer 320 may be substantially flat. Therefore, thicknessesof respective portions of the organic layer 320 may differ depending onshapes of the structures which are formed on the substrate 100. Thefirst portion of the organic layer 320 disposed at or on the pixeldefinition layer 180 may have the first thickness t1, the second portionof the organic layer 320 disposed in or at the separation area SA mayhave the second thickness t2, and the third portion of the organic layer320 disposed at or on an edge of the display 200 where the pixeldefinition layer 180 is not disposed may have the third thickness t3. Assuch, the third thickness t3 may be greater than the first thickness t1and less than the second thickness t2. The third thickness t3corresponds to a portion (e.g., the third portion of the organic layer320) that is disposed on an insulation layer which is disposed at theedge of the display 200.

The second inorganic layer 330 may be disposed on the organic layer 320.The second inorganic layer 330 may cover the organic layer 320, and theend of the second inorganic layer 330 may be disposed on the firstinorganic layer 310, which is disposed to cover the top of the dam 400and a side surface opposite to the direction of the display 200 (e.g., afirst portion of the second inorganic layer 330 may be disposed on thesecond portion of the first inorganic layer 310 that covers the secondside surface 400 b of the dam 400 and a second portion of the secondinorganic layer 330 may be disposed on the third portion of the firstinorganic layer 310 that covers the top 400 c of the dam 400). Thedistal end of the second inorganic layer 330 may contact the substrate200, and a sealing force is enhanced by a multi-layer structure of thefirst inorganic layer 310, the organic layer 320, and the secondinorganic layer 330 of the encapsulation layer 300.

Generally, in manufacturing an organic light-emitting display apparatus,a display may be formed by using a mask. In depositing each layer of thedisplay with the mask, because the mask may sag, scratches may occur dueto contact between the mask and a pixel definition layer portion whichprotrudes the most from the display, thus leaving particles on a surfaceof the mask. The particles are transferred to another panel in amanufacturing process of forming a plurality of layers with one mask.When such an operation is repeated, the particles make the surface ofthe mask non-uniform, and a scratch or scratches of the display 200 areprogressively deepened. Also, when the particles are of a certain sizeor larger, an encapsulation layer cannot normally seal the display dueto the particles, and a defect is caused by external moisture.Particularly, in areas progressively closer to the edge of the display,the thickness of an organic layer of the encapsulation layerprogressively decreases by the spread of an organic insulation material.Thus, a probability that particles attached to a planarization layerdisposed at an edge of the display will cause a small defect increases.

Therefore, in the organic light-emitting display apparatus according toone or more exemplary embodiments of the present invention, the heightof the dam 400 outside the display 200 may be higher than that of theplanarization layer 170, and thus, a thickness of the organic layerdisposed in the edge of the display 200 and the peripheral area PA ofthe substrate 100 may be formed relatively thick. Therefore, in amanufacturing process, particles attached to the edge of the display 200may be buried or contained or deposited in the second portion of theorganic layer 320 having the second thickness t2 or in the third portionof the organic layer 320 having the third thickness t3, therebyminimizing or reducing a defect of a sealing force of the encapsulationlayer 300.

As described above, according to the one or more of the above exemplaryembodiments, an organic light-emitting display apparatus with anenhanced sealing force and a method of manufacturing the same areimplemented.

It should be understood that exemplary embodiments described hereinshould be considered in a descriptive sense only and not for purposes oflimitation. Descriptions of features or aspects within each exemplaryembodiment should typically be considered as available for other similarfeatures or aspects in other exemplary embodiments.

While one or more exemplary embodiments have been described withreference to the figures, it will be understood by those of ordinaryskill in the art that various changes in form and details may be madetherein without departing from the spirit and scope as defined by thefollowing claims.

What is claimed is:
 1. An organic light-emitting display apparatuscomprising: a substrate; a display on the substrate; a dam outside thedisplay and spaced from the display, the dam having a stackedmulti-layer structure and having a first side surface that faces thedisplay, a second side surface opposite to the display, and a top; agroove in a separation area between the display and the dam; and anencapsulation layer comprising a first inorganic layer and an organiclayer on the first inorganic layer, the first inorganic layer coveringthe display and extending along an inner surface of the groove, and anend of the organic layer being contained in the groove.
 2. The organiclight-emitting display apparatus of claim 1, wherein a first portion ofthe first inorganic layer covers the first side surface of the dam, asecond portion of the first inorganic layer covers the second sidesurface of the dam, and a third portion of the first inorganic layercovers the top of the dam.
 3. The organic light-emitting displayapparatus of claim 2, further comprising a second inorganic layer on theorganic layer, wherein a first portion of the second inorganic layer ison the second portion of the first inorganic layer and a second portionof the second inorganic layer is on the third portion of the firstinorganic layer.
 4. The organic light-emitting display apparatus ofclaim 3, wherein a top of the organic layer is substantially flat. 5.The organic light-emitting display apparatus of claim 1, wherein the damcomprises a recessed portion at the top of the dam.
 6. The organiclight-emitting display apparatus of claim 5, wherein the organic layeris not on the second side surface of the dam.
 7. The organiclight-emitting display apparatus of claim 1, further comprising: a metallayer on a side of the display, the metal layer being configured tosupply power to the display; and an insulation layer under the metallayer, wherein the separation area exposes the metal layer or theinsulation layer.
 8. The organic light-emitting display apparatus ofclaim 1, wherein the display comprises: a thin film transistor on thesubstrate; a pixel electrode electrically connected to the thin filmtransistor; a pixel definition layer covering an edge of the pixelelectrode and exposing a portion of the pixel electrode; an intermediatelayer on the pixel electrode, the intermediate layer comprising anemission layer; and an opposite electrode opposite to the pixelelectrode, and wherein the dam comprises: a first layer extending in adirection parallel to the plane of the substrate and comprising anorganic insulation material; and a second layer on the first layer andcomprising a material that is the same as a material of the pixeldefinition layer.
 9. The organic light-emitting display apparatus ofclaim 8, wherein a height of the dam from a top of the substrate to thetop of the dam is greater than a height from the top of the substrate toa bottom of the pixel definition layer.
 10. The organic light-emittingdisplay apparatus of claim 8, wherein a first portion of the organiclayer at the pixel definition layer has a first thickness, a secondportion of the organic layer at the separation area has a secondthickness, and a third portion of the organic layer at an edge of thedisplay without the pixel definition layer thereon has a thirdthickness, and wherein the third thickness is greater than the firstthickness and less than the second thickness.
 11. The organiclight-emitting display apparatus of claim 8, further comprising aninsulation layer that covers the thin film transistor and planarizes atop of the thin film transistor, wherein the pixel definition layer ison the insulation layer, wherein a first portion of the organic layer atthe pixel definition layer has a first thickness, a second portion ofthe organic layer at the separation area has a second thickness, and athird portion of the organic layer at the insulation layer at an edge ofthe display has a third thickness, and wherein the third thickness isgreater than the first thickness and less than the second thickness. 12.A method of manufacturing an organic light-emitting display apparatus,the method comprising: forming a display on a substrate; forming a damoutside the display, the dam being spaced from the display and having astacked multi-layer structure; and forming an encapsulation layer, theencapsulation layer comprising: a first inorganic layer covering thedisplay and extending along an inner surface of a groove; and an organiclayer on the first inorganic layer, wherein the groove is at aseparation area between the display and the dam, wherein an end of theorganic layer is contained in the groove, and wherein the dam has afirst side surface that faces the display, a second side surfaceopposite to the display, and a top.
 13. The method of claim 12, whereina first portion of the first inorganic layer covers the first sidesurface of the dam, a second portion of the first inorganic layer coversthe second side surface of the dam, and a third portion of the firstinorganic layer covers the top of the dam.
 14. The method of claim 13,wherein the forming of the encapsulation layer comprises forming asecond inorganic layer on the organic layer, and wherein a first portionof the second inorganic layer is on the second portion of the firstinorganic layer and a second portion of the second inorganic layer is onthe third portion of the first inorganic layer.
 15. The method of claim14, wherein a top of the organic layer is substantially flat.
 16. Themethod of claim 12, further comprising: forming a metal layer on a sideof the display, the metal layer being configured to supply power to thedisplay; and forming an insulation layer under the metal layer, whereinthe separation area exposes the metal layer or the insulation layer. 17.The method of claim 12, wherein the forming of the display comprises:forming a thin film transistor on the substrate; forming a pixelelectrode that is electrically connected to the thin film transistor;forming a pixel definition layer, which covers an edge of the pixelelectrode and exposes a portion of the pixel electrode; forming anintermediate layer on the pixel electrode, the intermediate layercomprising an emission layer; and forming an opposite electrode oppositeto the pixel electrode, and wherein the forming of the dam comprises:forming a first layer that extends in a direction parallel to the planeof the substrate and comprising an organic insulation material; andforming a second layer on the first layer, the second layer comprising amaterial that is the same as a material of the pixel definition layer,the second layer and the pixel definition layer being formedconcurrently.
 18. The method of claim 17, wherein a height of the damfrom a top of the substrate to the top of the dam is greater than aheight from the top of the substrate to a bottom of the pixel definitionlayer.
 19. The method of claim 12, wherein a first portion of theorganic layer at the pixel definition layer has a first thickness, asecond portion of the organic layer at the separation area has a secondthickness, and a third portion of the organic layer at an edge of thedisplay without the pixel definition layer thereon has a thirdthickness, and wherein the third thickness is greater than the firstthickness and less than the second thickness.
 20. The method of claim12, wherein the forming of the display and the forming of the dam areconcurrently performed.